The provider of the Apache Cassandra database has more than 500 customers, including Safeway, Target and Netflix, for which DataStax helps handle 10 million transactions a second. DataStax works with 30% of the 100 biggest companies in the world and has secured partnerships with Accenture, Google and Microsoft. "Cassandra is reinventing the database layer," says CEO Billy Bosworth. "We have the feeling that we've caught a shooting star." DataStax has a ballpark revenue run rate of $50 million to $100 million.